Setup a Solidity project using Hardhat and Typescript
May 29, 2022-4 min read
Let's see how we can setup a new Solidity project for smart contracts development, using Hardhat and Typescript.
What is Hardhat
Hardhat is a development environment that aims to provide all neccessary tools so that you can develop, test and deploy Ethereum software. Beside Hardhat there is Truffle. Truffle and Hardhat are the most famous enviornments for developing Etherum software. Both have their advantages and strenghts, but the trend is, that more and more devs are using Hardhat. Let's get started!
Creating the project
First, create a new node project by typing the following in a terminal:
$ npm init --yes
Then, add the hardhat depencency:
$ npm install --save-dev hardhat
Using Hardhat to generate a sample project
By far the easiest way to get started with Hardhat, is to use its CLI to generate a sample project for us:
$ npx hardhat
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Create an advanced sample project that uses TypeScript and then choose Y on the questions.
Going through the project structure
We now have a basic project structure, with a sample contract and a basic test
/contracts: This is where you put your smart contracts, as .sol files.
/test: Here you can put all your tests. Hardhat is using chai and ethers. Chai as test-runner and ethers to interact with the ethereum blockchain.
/scripts: Here you can put your automation scripts, maybe one script for deploying to rinkeby testnet and one for local testnet ? You decide :)
hardhat.config.ts: This is the place where you configure the HRE (Hardhat Runtime Enviornment). The HRE is an object containing all the functionality that Hardhat exposes when running a task, test or script. You can use it anywhere across the project with const hardhat = require("hardhat"). In the config we also define tasks; one example task is also provided by Hardhat for listing all accounts.
Compiling, testing and delpoying a contract
To compile the smart contracts of our project we can run:
$ npx hardhat compile
Generating typings for: 2 artifacts in dir: typechain for target: ethers-v5Successfully generated 5 typings!Compiled 2 Solidity files successfully
Hardhat will compile all .sol files against the Solidity version that is configured in the hardhat.config.ts:
The compiled artifacts will be saved in the
artifacts/ directory. Since we are also using Typescript, the
typechain/ directory will contain the Typescript types of our contracts.
To test you smart contracts, simply run:
$ npx hardhat test
No need to generate any newer typings.GreeterDeploying a Greeter with greeting: Hello, world!Changing greeting from 'Hello, world!' to 'Hola, mundo!'✔ Should return the new greeting once it's changed (385ms)1 passing (385ms)
Hardhat comes built-in with Hardhat Network, a local Ethereum network node designed for development. It allows you to deploy your contracts, run your tests and debug your code. On a new terminal, type:
$ npx hardhat node
Started HTTP and WebSocket JSON-RPC server at http://127.0.0.1:8545/Accounts========WARNING: These accounts, and their private keys, are publicly known.Any funds sent to them on Mainnet or any other live network WILL BE LOST.Account #0: 0xf39Fd6e51aad88F6F4ce6aB8827279cffFb92266 (10000 ETH)Private Key: 0xac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80......
The hardhat testnet is now running at
We can now use the sample
deploy.ts script to deploy our contracts.
$ npx hardhat run --network localhost scripts/deploy.ts
web3_clientVersioneth_chainIdeth_accountseth_blockNumbereth_chainId (2)eth_estimateGaseth_getBlockByNumbereth_feeHistoryeth_sendTransactionContract deployment: GreeterContract address: 0xe7f1725e7734ce288f8367e1bb143e90bb3f0512Transaction: 0xf35ffcaaa97d66392192e1f2f422f9ddeb489771c86668ebc060142a95de569aFrom: 0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266Value: 0 ETHGas used: 497026 of 497026Block #2: 0xa87bf346afe7de493c6a5dc7bd859b725d6c8774ce7dce50a906a2575312c84bconsole.log:Deploying a Greeter with greeting: Hello, Hardhat!eth_chainIdeth_getTransactionByHasheth_chainIdeth_getTransactionReceipt
Congratulations, the sample smart contract Greeter is now deployed at the address
0xe7f1725e7734ce288f8367e1bb143e90bb3f0512 on the local testnet!
In the course of this tutorial, we saw how to setup a new project for solidity development. We created our project using Hardhat, we compiled and tested a smart contract. Finally, we deployed the smart contract on a locally running testnet.
Source for this tutorial can be found at https://github.com/gedim21/blog/tree/master/hardhat.